Many electronic devices emit unintended and, generally undesirable, electromagnetic (EM) radiation. Private, national or international standards or testing groups have developed, and continue to develop, various testing procedures and/or standards related to the magnitude of such emissions. Such standards or testing can be used by potential purchasers for comparison purposes and/or for regulating the sale or use of various electronic devices. One recent trend has been for such testing or standards to be applied at increasingly higher-frequency ranges of the electromagnetic spectrum. A common standard that is implemented for testing is “FCC Part 15” in the United States and CISPR (Comite International Special des Pertubation Radioelectriques) in many parts of the world. According to CISPR-B, radiated emissions from a disk drive must be below 47 dBmV/m in the frequency range from 250 MHz through 1 GHz. Similar limits exist for other frequencies in the frequency range from 30 MHz through 1 GHz. As clock frequencies of disk drives increase, testing is being done at higher frequencies such as 6 GHz and more.
Some standards or testing procedures are intended to provide an indication of the magnitude of an EM emission which occurs as a carried signal riding on a lower frequency continuous wave (CW) signal. In one procedure, the measurement of the electromagnetic spectrum is “quasi-peaked.” Generally speaking, in this procedure, the signal level is weighted based on the repetition frequency of the spectral components making up the signal. Accordingly, it would be useful to provide a method, system and/or apparatus such that quasi-peaks in the electromagnetic spectrum emissions from a disk drive are reduced, as compared to the level or magnitude of peaks in the absence of using such system, method or apparatus.